Wireless communications are enabled by various types of networks, including Universal Mobile Telecommunication System (UMTS) networks and Global System for Mobile communications (GSM) networks, for example. The various types of wireless communications networks include multiple base stations, referred to as Node Bs in UMTS networks, for exchanging communications with mobile devices operating within corresponding cells. The base stations or Node Bs are connected to a controller, such as a base station controller (BSC) or radio network controller (RNC), which is in turn connected to a Mobile Switching Center (MSC) within the core network. Also within the core network is a Gateway Mobile Location Center (GMLC), which is the first access point of location requests from external clients.
Conventional wireless communication services may include the feature of determining geographic positions or locations of mobile devices. For example, an emergency service responsive to “911” initiated at a mobile device may include estimating latitude and longitude of the mobile device in order to locate the device, which is particularly important when a distressed caller is otherwise unable to provide their present position. Geographic location of mobile devices may be determined by a location determination server in the wireless communication network, such as a serving mobile location center (SMLC), connected to base stations through a BSC in a GSM network, or a stand-alone SMLC (SAS) connected to Node Bs through an RNC of a UMTS network. The location determination server may determine the geographic location of a mobile device operating within the wireless communication network using positioning measurements from a global navigation satellite system (GNSS) provided by the mobile device or by using other network-oriented measurements (such as signal strength, arrival time, timing advance, etc).
A wireless communications network may include multiple access networks, each of which typically corresponds to a different carrier or network service provider. Accordingly, each access network providing geographic location determination services in a UMTS network, for example, includes an SAS dedicated to that access network. Currently communications standards, such as the Positioning Calculation Application Part (PCAP), incorporate this configuration, and thus limited information identifying network nodes involved in the location determination process is provided to the SAS, since it is anticipated that the network nodes are all in the same access network. Therefore, the SAS cannot service multiple access networks under conventional standards and implementations.
In a representative embodiment, a method is provided for processing requests by a stand-alone serving mobile location center (SAS), shared by multiple radio access networks in a wireless network, for determining locations of mobile devices within the wireless network. A positioning request message for a mobile device is received from a first radio network controller in a first radio access network of the multiple radio access networks. An originating point code (OPC) and a cell identifier are retrieved from the positioning request message. A mobile country code (MCC) and a mobile network code (MNC) corresponding to the first radio access network are determined based on the retrieved OPC. A serving network node communicating with the mobile device is identified using the cell identifier and the determined MCC and MNC.
In another representative embodiment, an apparatus is provided for processing requests to determine locations of mobile devices in a wireless network, the apparatus being shared by multiple radio access networks of the wireless network. The apparatus includes an interface module, a retrieval module, a determination module and a node identification module. The interface module is configured to receive a first positioning request message for a first mobile device from a first radio network controller in a first radio access network and to receive a second positioning request message for a second mobile device from a second radio network controller in a second radio access network. The retrieval module is configured to retrieve a first OPC and a first cell identifier from the first positioning request message. The determination module is configured to determine a first MCC and a first MNC corresponding to the first radio network based on the first retrieved OPC. The node identification module is configured to identify a first network node serving the first mobile device based on the first cell identifier and the first determined MCC and MNC.
In another representative embodiment, a computer readable medium is provided for storing code executable by a computer processor for processing requests by an SAS, shared by multiple radio access networks in a wireless network, to determine locations of mobile devices within the wireless network. The computer readable medium includes a retrieving code segment for retrieving an OPC and a cell identifier from a positioning request message received from a first radio network controller in a first radio access network of the multiple radio access networks, the positioning request message corresponding to a mobile device. The computer readable medium also includes a determining code segment for determining an MCC and an MNC corresponding to the first radio access network based on the retrieved OPC, and an identifying code segment for identifying a serving network node communicating with the mobile device using the cell identifier and the determined MCC and MNC.